<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>选择器</title>
	<style>
		#first{
			color: red;
		}
		.one{
			color: blue;
		}
		p span{
			color: yellow;
		}
		p span:hover{
			color: red;
		}
		i,b{
			color: green;
		}
		*{
			font-family: "宋体";
		}
	</style>
</head>
<body>
	<i>我是i</i>
	<b>我是b</b>
	<p id="order-id">学并思1</p>
	<p>学并思2</p>
	<p>学并思3</p>
	<p class='one'>学并思4</p>
	<p class='one'>学并思4</p>
	<p class='one'>学并思4</p>
	<p class='one'>学并思4</p>
	<p>
		<span>我是span1</span>
	</p>
	<span>我是span2</span>
</body>
</html>